vfs: make the string hashes salt the hash

We always mixed in the parent pointer into the dentry name hash, but we
did it late at lookup time.  It turns out that we can simplify that
lookup-time action by salting the hash with the parent pointer early
instead of late.

A few other users of our string hashes also wanted to mix in their own
pointers into the hash, and those are updated to use the same mechanism.

Hash users that don't have any particular initial salt can just use the
NULL pointer as a no-salt.

Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index aaf7bd0cbae2..d6935a9e8fdd 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -232,7 +232,7 @@ int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int le
 	 * in a page cache page which kmemleak does not scan.
 	 */
 	kmemleak_not_leak(string->name);
-	string->hash = full_name_hash(name, len);
+	string->hash = full_name_hash(NULL, name, len);
 	return 0;
 }
 
@@ -497,7 +497,7 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 		if (filename.len == 2 && filename.name[1] == '.')
 			return;
 	}
-	filename.hash = full_name_hash(filename.name, filename.len);
+	filename.hash = full_name_hash(parent, filename.name, filename.len);
 
 	dentry = d_lookup(parent, &filename);
 again: